Spiked golf sole

ABSTRACT

AN ELASTOMERIC GOLF SHOE HAVING FRUSTO-CONICAL SPIKES OF TITANIUM-COATED ALUMINUM OXIDE WITH THEIR BASES MOLDED INTO THE SOLE AND THEIR TAPERED END PORTIONS PORJECTING THEREFROM, THE SOLE SURFACE AREAS SURROUNDING SAID PROJECTING PORTIONS BEING RELIEVED SO AS TO TRANSFER FLEXING CAUSED BY FORCES APPLIED TO SAID PROPJECTING PORTIONS RADIALLY OUTWARD THEREOF, SAID SPIKES BEING BONDED TO SAID ELASTOMERIC MATERIAL BY A COMBINATION OF COMPATIBLE CEMENTS WHICH WHEN SUBJECTED TO MOLDING HEAT MAKE A PERMANENT BOND BETWEEN THE TITANIUM COATING OF THE SPIKES AND THE ELASTOMERIC MATERIAL.

Get. 5, 1971 T. D. CALVIN ET AL 3,609,889

SPIKED GOLF SOLE Filed July 14, 1969 2 Sheets-Sheet 1 [NV/5N! HRSTIMOTHY D. CALVIN I BY EWAR GU IS I4 |lI .7I A w 1 4 28 mm 3 MAWATTORNEYS (Data 5, 1971 T. D. CALVIN ETAL SPIKED GOLF some Filed July14, 1969 2 Sheets-Sheet 3 IN V/;'N/ (IRS TIMOTHY D. CALVIN 7EPWARD 6%5 9I ATTORNEYS United States Patent Oifice 3,609,889 SPIKED GOLF SOLETimothy D. Calvin, Akron, and Edward Gulbis, Barberton, Ohio, assignorsto Bearfoot Corporation, Wadsworth, Ohio Filed July 14, 1969, Ser. No.841,378 Int. Cl. A43c 15/00 U.S. CI. 36-67 R 13 Claims ABSTRACT OF THEDISCLOSURE An elastomeric golf shoe sole having frusto-conical spikes oftitanium-coated aluminum oxide with their bases molded into the sole andtheir tapered end portions projecting therefrom, the sole surface areassurrounding said projecting portions being relieved so as to transferflexing caused by forces applied to said projecting portions radiallyoutward thereof, said spikes being bonded to said elastomeric materialby a combination of compatible cements which when subjected to moldingheat make a permanent bond between the titanium coating of the spikesand the elastomeric material.

BACKGROUND OF THE INVENTION Conventional golf shoe soles haying metalspikes require screw threaded sockets embedded in the sole into whichthe threaded metal spikes having relatively large bases are screwed.Thus the number of spikes which can be mounted in a sole and heel islimited by the areas of the bases, with the result that fewer spikes areemployed than would be desirable for optimum support and traction.Moreover, there is always a danger of cross threading in installing thespikes which may require replacement of a socket and add to themanufacturing cost.

Further, conventional metal spikes wear off rather rapidly due to thenecessity for the wearer to tread on hard surfaces such as cement andgravel walkways and the like, out of doors, and in and to and fromlocker rooms and other facilities. Such wear results in burrs and sharpedges on the spikes which make them injurious to carpeting walked overto and from the locker and clubhouse rooms. Also, such wear requiresfairly frequent replacement of the spikes with the attendant likelihoodof cross threading.

An additional disadvantage resulting from the use of conventional spikesis that the large metal bases thereof tend to compress or hammer thegolf course greens as they are constantly walked upon, thus tending toharden the greens in spots and impede grass growth thereon.

SUMMARY OF THE INVENTION It is an object of the present invention toprovide a novel and improved spiked golf shoe sole which overcomes thedisadvantages of conventional spiked shoes, and is simple andinexpensive to manufacture.

Another object is to provide a novel spike design and construction whichis molded in place with the sole and does not require replacement.

A further object is to provide a novel spike design which is soconstructed that more spikes per sole can be used, thereby obtainingbetter support and traction.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a bottom plan view of a moldedshoe sole embodying the invention.

FIG. 2 is a top plan view thereof.

FIG. 3 is an enlarged section thereof as on line 3-3 of FIG. 1, with amidsole applied to the top surface.

FIG. 4 is a longitudinal sectional view through the mold for making thesole, showing the mold inserts for positioning the novel spikes.

Patented Oct. 5, 1971 FIG. 5 is an enlarged fragmentary sectional viewshowing one of the novel spikes as molded in the sole.

FIG. 6 is a detached perspective view of one of the novel spikes.

DESCRIPTION OF A PREFERRED EMBODIMENT The shoe sole indicated generallyat 10 is molded from elastomeric material such as synthetic rubber ofthe styrene butadiene type. Although other types of synthetic rubber ornatural rubber may be used, we have found that a synthetic rubbercompound, preferably of a high silica content and having a controlleddurometer hardness of approximately 70 has given excellent results.

The novel spikes 13 molded into the sole are substantially conical witha circular base portion 14 having a rounded periphery and a shallowrecess 15 at the center. Preferably, the side wall 16 of the spike iscurved inwardly or concave as shown, and the small end has asubstantially flat surface 17. The material of which the spikes are madeis substantially pure corundum (aluminum oxide) and is extremely hardand wear-resistant to the extent that such spikes in a golf shoe willlast at least as long as the shoe with substantially no wearing down ofthe surfaces 17.

The base portion 14 and the adjacent conical portion of each spike 13 isembedded in the sole, and in the sole portion 12 a frusto-conicalprojection enlargement or button 18 encases the base portion 14 of eachspike so as to securely support the spike when its projecting end iswalked upon and subjected to lateral forces. Similarly, while the heelportion 11 is hollow, the bases 14 of the spikes 13 therein are encasedin rounded bosses or buttons 19 and 19, with transverse bridge portions20 and 20' connecting laterally opposite bosses 19, the top surfaces ofthe bridges 20 and 20' being preferably coplanar with the upperperiphery of the heel so as to provide a firm support for the heelportion 21 of a midsole 22 applied to the top of sole 10 (FIG. 3). Themidsole 22 preferably is substantially the same or slightly greater inthickness than the buttons 18 and is provided with circular openings 23for surrounding the buttons.

In the bottom surface of sole portion 12 and the heel portion 11, anannular groove 24 is provided concentric with and spaced radially fromeach spike. The purpose of the groove is to transfer the flexing arearadially outward from the spike, so that the high stresses to which thespike is subjected are not concentrated at the joint between the spikeand the surrounding rubber of the sole.

As shown in FIG. 4, the mold for forming the spiked sole 10 comprisestwo mating parts or plates 26 and 27 forming at least one cavity for thecombination sole and heel. The bottom plate 26 has counterbored holes 28and 28', with the larger portions 29 thereof opening into the inner faceof the plate, and positioned at the predetermined locations for thespikes. Hardened tool-steel inserts 30 are tightly fitted into the holes29, each insert having a conical recess 31 therein for wedgablyreceiving the tapered end portion of a spike 13. As best seen in FIG. 5,the inner end of each insert 30 has an annular rib 32 around itsperiphery for forming the annular groove 24 in the bottom surface of thesole.

The top mold plate 27 is provided with frusto-conical recesses 33registering with the inserts 30* in the sole portion of the mold forforming the buttons 18 surrounding the base portions 14 of the spikes inthe molded sole. In the heel portion of the mold a metal insert plate 34is attached to the inner face ofthe top plate as by screws (not shown).The insert 34 has an outer periphery shaped to form the heel cavity 35with recesses 36 and 36' on its exposed face to form the bosses 19 and19' encasing the bases of the spikes 13 in the molded heel, and with 3through slots 37 and 37' to form the bridge portions and 20'.

In order to make a good bond between the extremely hard and smoothsurface of the corundum spikes 13 with the rubber of the sole 10, thespikes are coated with titanium by a special process developed and ownedby Coors Porcelain Company of Golden, Colo. The process of applying thetitanium coating to the spikes per se forms no part of the presentinvention. Sutfice it to say that the titanium coating overcomes theextreme smoothness of the corundum so that the spike surf-aces can befully bonded to the rubber with suitable cements.

We have discovered that best results are obtained by using twocompatible resin cements, one as a primer and the other as a finishcoating on the spikes. Two such cements are manufactured and sold byHughson Chemical Company, Division of Lord Corporation, Erie, Pa., underthe trade names Chemlok 205 and Chemlok 220. The exact composition ofthese cements is not available, but they are described generally asbeing mixtures of polymeric compounds and fillers in a solvent system.

We use Chemlok 205 as the primer coating by diluting it in a mixingcontainer with about 20% methyl ethyl ketone (MEK) to bring theviscosity to 29 plus or minus 1 second at 70 -F. when checked with a No.1 Zahn cup. The Chemlok 220 is used as the finishing coat is dilutedwith about 20% toluol to bring the viscosity to 29 plus or minus 1second at 70 F. when checked with a No. 2 Zahn cup.

A thin coating of continuously agitated Chemlok 205 is first applied ina suitable manner, as by brushing, dipping or spraying, to the baseportion and so much of the conical portion of the spikes as will beencased in the rubber sole, excess cement removed, and the coatingthoroughly dried to leave a coating preferably 0.3 to 0.5 mil thickness.A thin unifo-r-m coating of the Chemlok 220 is then applied from acontinuously agitated supply in a similar manner and dried. The coatedspikes are then positioned in the mold inserts 30, substantially all ofthe coated portion projecting into the mold cavity for bonding with therubber sole during vulcanization. The uncured rubber blank which is toform the sole is then placed in the cavity, the mold closed in avulcanizing press and the blank molded and cured. During the curingprocess the Chemlok cements form a complete and permanent bond betweenthe elastomeric sole and the titanium coating of the spikes, such as towithstand stresses during walking on the spikes, in all kinds of weatherconditions. Any tendency of cracking of the sole material around thespikes is prevented by the concentric stress-relieving grooves aroundthe spikes.

The substantially conical shape of the novel spikes with thefrustoconical buttons surrounding the bases provides optimum stabilityand support for the spikes under all conditions. Because the bases ofthe spikes are relatively small as compared with the metal bases ofconventional screw type spikes, more spikes can be distributed over thesole and heel area, thereby obtaining better distributed support andmore traction. Reference to FIGS. 1 and 2 makes it apparent that atleast two additional spikes can be arranged on the sole area as comparedwith conventional spikes.

Further, the absence of the large metal bases of conventional spikes onthe bottom surface of the sole results in less hammer and damage to thegolf greens as they are walked upon.

Finally, the extremely hard and wear-resistant properties of the spikesprovide a durable spiked golf shoe sole which does not requirereplacement of the spikes, with attended cross threading as inconventional spikes, and

in which the spikes do not become uneven or burred so I as to damagecarpeting or other floor surfaces.

We claim:

1. An elastomeric golf shoe sole having substantially conical spikes ofcorundum with their bases molded within the sole and their opposite endsprojecting therefrom, said spikes being coated with titanium and bondedto said elastomeric material by polymeric cement which forms a permanentbond when subjected to molding temperatures for curing said elastomericmaterial.

2. An elastomeric golf shoe sole as in claim 1, in which the elastomericmaterial is a styrene butadiene synthetic rubber compound of high silicacontent having a durometer hardness of about 70.

3. An elastomeric golf shoe sole as in claim 1, in which the areas ofthe sole surface surrounding the spikes have concentric stress-relievinggrooves spaced radially outward from said spikes.

4. An elastomeric golf shoe sole as in claim 1, in which the bondbetween the spikes and the elastomeric material is formed by acombination of two compatible polymeric cements.

5. An elastomeric golf shoe sole as in claim 1, in which the bases ofthe spikes are encased in bosses formed on the upper surface of thesole.

6. An elastomeric golf shoe sole as in claim 2, in which the areas ofthe sole surface surrounding the spikes have concentric stress-relievinggrooves spaced radially outward from the spikes.

7. An elastomeric golf shoe sole as in claim 2, in which the bondbetween the spikes and the synthetic rubber compound is formed by acombination of two compatible polymeric cements.

-8. An elastomeric golf shoe sole as in claim 4, in which the bondformed between the spikes and the elastomeric material consists of aprimer cement coat and a finish cement coat on the spikes comprising twocompatible mixtures of polymeric compounds and fillers in a solventsystem.

9. An elastomeric golf shoe sole as in claim 7, in which the bond formedbetween the spikes and the synthetic rubber compound consists of aprimer cement coat and a finish cement coat on the spikes comprising twocompatible mixtures of polymeric compounds and fillers in a solventsystem.

10. An elastomeric sole for a shoe, said sole having a bottom surfaceand comprising, a plurality of spike means partially embedded in thebottom surface so that a portion of said spike means extends therefromfor contact with the ground, and stress-relieving means Within saidsole, said stress-relieving means being a groove formed within saidbottom surface and extending around said spike means so that the highstresses to which said spike means is subjected when in contact with theground are transferred to said stress-relieving means.

11. An elastomeric sole as in claim 10, wherein said groove is annularand spaced radially outward from and concentric with said spike means.

12. A shoe having an elastomeric sole comprising, a plurality of spikeshaving base portions embedded within said sole and projecting portions.extending outwardly therefrom, said sole having groove means formedtherein, said groove means being spaced from and extending around saidspikes so that stress-creating forces applied to said projectingportions of said spikes are transferred to said sole at said groovemeans.

13. A shoe as in claim 12, wherein said base portions of said spikes arecircular and said groove means is spaced radially from and concentricwith said spike means.

References Cited UNITED STATES PATENTS 3,343,285 9/1967 Kowal 36-67 D3,486,249 12/1969 Bernier et a1. 36-67 D 3,328,901 7/1967 Strickland362.5 3,410,005 11/1968 Szerenyi 36-2.5 3,452,378 7/1969 Ferreira 12-1423,480,979 12/1969 Gammons 12-142 PATRICK D. LAWSON, Primary Examiner

